What is the term used for the half-moon at the base of the nails?

The half-moon shape at the base of the nails is referred to as the lunula. This anatomical feature is visible at the base of the nail plate and is a whitish area that can often be seen on the fingernails of most individuals. The lunula is the visible part of the nail matrix, which lies beneath the skin and is crucial for nail growth.

Its distinctive appearance is due to the thicker layer of keratin in this area, which makes it appear lighter in color compared to the rest of the nail. The lunula is also a key indicator of nail health; abnormalities in its size or coloration can signal underlying health conditions.

Other terms listed, like the matrix, nail bed, and hyponychium, refer to different parts of the nail anatomy. The matrix is the tissue beneath the base of the nail where growth occurs. The nail bed is the skin beneath the nail plate, and the hyponychium is the area of skin underneath the free edge of the nail. While all these structures play important roles in nail health and growth, the term specifically describing the half-moon shape at the nail's base is lunula.